Chess Fork Trainer

About visualization training, I would like to mention the excellent software of Chess Fork Trainer. It is a very useful piece of software that was inspired by De La Maza's 'vision drills'. There are a lot of different options, the idea is to find the safe squares to fork king and piece. One can have a fixed square king (to train with c8 or g8 kings) or random. This is a great software which I find extremely helpful. Here is how a completed exercise looks